Light generating apparatus and method of controlling the same

ABSTRACT

A light beam generating apparatus and method of controlling the same is provided. The light beam generating apparatus may include a light source, a beam expander collimating a light beam emitted from the light source, an optical shutter selectively transmitting a light beam transmitted through the beam expander, and a focusing lens focusing a light beam transmitted the optical shutter. The optical shutter in the light generating apparatus can selectively transmit a light beam based on on/off control of the optical shutter on a pixel-by-pixel basis. This may permit one-dimensional, two-dimensional and three-dimensional nano patterns having various periods and directions to be manufactured.

CROSS-REFERENCE TO RELATED APPLICATION

This U.S. non-provisional patent application claims priority under 35U.S.C. §119 to Korean Patent Application No. 10-2008-0089334, filed onSep. 10, 2008, the entire contents of which are incorporated herein byreference.

BACKGROUND

1. Field

Example embodiments relate to light generating apparatuses and methodsof controlling the same, for example, a light generating apparatus thatmanufactures a one-dimensional, two-dimensional, or three-dimensionalnano pattern having various periods and/or directions, and a method ofcontrolling the same.

2. Description of the Related Art

A diffracting grating (e.g., a device for diffracting light to a desireddirection by using diffraction and/or interference) may be formed byengraving various parallel lines at narrow intervals in a flat glass ora concave metal plate. When light is radiated to a diffracting grating,the transmitted and/or reflected light may cause a light spectrumaccording to the wavelength of the light.

The diffracting grating may disperse light better than a prism. Also,the diffracting grating's spectrum band may not decrease as it spanstoward the red side, which may have a relatively long wavelength.Instead, the diffracting grating's spectrum bands may be uniform fromthe red regions on through to the violet regions (e.g., all thewavelengths in visible light). Also, the spectrum bands of 1^(st),2^(nd) and/or 3^(rd) orders may be exhibited in parallel.

Conventionally, laser beam interference emitted from a light source maymanufacture a diffraction grating. Such a conventional manufacturingmethod may control the grating period of a diffraction grating. However,the direction of the grating itself, once made, is geometricallyunchangeable. Thus, the direction of the diffraction, which may becaused by chromatic dispersion, may not be controlled.

To address such concerns, a dot matrix system that may freely controlgrating period and/or direction of a diffraction grating has beenproposed. In such a system, a light beam may be transmitted in variousdirections without chromatic dispersion, which may permit a desiredlight distribution.

In the dot matrix system, a diffractive optical element (DOE) pattern isused in order to form a diffraction grating pattern. In addition, amotor driver rotating the DOE pattern may change the grating directionof a diffraction grating. However, since the motor driver may operate ata low speed, patterning time may increase. In addition, a method ofelectrically changing a DOE pattern has also been proposed in order tochange the grating direction of a diffraction grating. However, thismethod may only manufacture a previously calculated pattern.

SUMMARY

Example embodiments provide light generating apparatuses, and methods ofcontrolling of the same, to manufacture a nano pattern having variousperiods and/or directions.

According to example embodiments, a light generating apparatus may havea light source, a beam expander, an optical shutter, and/or a focusinglens. The light source may emit a light beam. The beam expander may atleast one of enlarge and/or collimate the light beam. The opticalshutter may selectively transmit a light beam transmitted through thebeam expander to form at least two light beams. The focusing lens mayfocus at least two light beams on a same location such that the at leasttwo light beams interfere with each other.

In further example embodiments, a first portion of the optical shuttermay transmit the light beam transmitted through the beam expander,and/or a second portion of optical shutter may not transmit the lightbeam transmitted through the beam expander. Also, the optical shuttermay include a plurality of pixels, such that the optical shutterselectively transmits a light beam according to an on/off control, theon/off control operating on a pixel-by-pixel basis. The on/off controlmay include at least two optical openings formed in the optical shuttersuch that the light beam transmitted through the beam expander isselectively transmitted through the openings. Also, the on/off controlmay adjust at least one of (i) at least one of the at least twoopenings, (ii) an interval between the at least two openings, (iii)sizes of the at least two openings, (iv) locations of the at least twoopenings, and/or (v) shapes of the at least two openings. The focusinglens may focus a light beam transmitted through the focusing lens on aphotosensitive layer, and/or may form a grating pattern of a diffractiongrating using an interference pattern formed on the photosensitive layerby interference of the focused light beam. A period of the diffractiongrating may be controlled according to an interval between at least twoopenings formed in the optical shutter. A direction of the diffractiongrating may be controlled according to rotation of at least two openingsformed in the optical shutter.

In further example embodiments, the optical shutter may further includea spatial light modulator. The beam expander may further include acollimating lens changing the light beam emitted from the light sourceinto a parallel light beam. The light generating apparatus may furtherinclude a plurality of light sources and/or a plurality of opticalshutters, the plurality of light sources and/or the plurality of opticalshutters may be arranged in an array shape.

In another example embodiment, a light generating apparatus may furtherinclude a beam splitter. The beam splitter may have surfaces facing thebeam expander, the optical shutter and/or the focusing lens, providingthe light beam emitted from the beam expander to the optical shutter,and/or providing the at least two light beams emitted from the opticalshutter to the focusing lens. The light generating apparatus may alsoinclude a polarizer polarizing the at least two light beams provided bythe beam splitter, the polarizer being between the beam splitter and/orthe focusing lens. Also, the beam splitter may further include apolarization beam splitter. The optical shutter may further include atleast one of a liquid crystal on silicon (LCoS) and a digital micromirror device (DMD).

In an example embodiment of a diffraction grating, the diffractiongrating may include a photosensitive layer and/or a nano pattern formedon the photosensitive layer. The photosensitive layer may receive atleast two light beams, an optical shutter at least one of (i)selectively transmits and (ii) selectively reflects the at least twolight beams. The nano pattern may be formed by focusing an interferencepattern on the photosensitive layer, the interference pattern formed byinterference generated by the at least two light beams. Also, an on/offcontrol may control the optical shutter to adjust a period and/ordirection of the nano pattern.

In an example embodiment a light generating apparatus control method, alight beam may be emitted from a light source, the light beam may beenlarged and/or collimated, the transmitted collimated light may beselectively reflected and/or selectively transmitted to form at leasttwo light beams, and the two light beams may be focused on a samelocation such that the two light beams may interfere with each other.The reflecting and/or transmitting may be performed on a pixel-by-pixelbasis by an on/off control, the on/off control controlling an opticalshudder including a plurality of pixels. The reflecting and/ortransmitting may be performed by controlling an optical shutter, onwhich at least two openings are to be formed, so that only a light beamincident on the openings is transmitted through the optical shutter. Infurther example embodiments, the interval between the at least twoopenings may be controlled. Also, the at least two opening on theoptical shutter may be rotated. The light beam may be divided by a beamsplitter, and the divided beam may be selectively reflected by anoptical shutter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying figures provide a further understanding of exampleembodiments along with the description of the example embodiments. Inthe figures:

FIG. 1 illustrates a light generating apparatus according to an exampleembodiment;

FIGS. 2A through 2E illustrate various patterns of an opening in anoptical shutter according to an example embodiment;

FIGS. 3A through 3E illustrate patterns of diffraction gratings formedby light transmitted through the openings of FIGS. 2A through 2Eaccording to an example embodiment;

FIG. 4 illustrates a light generating apparatus according to an exampleembodiment;

FIG. 5 illustrates openings displayed on an optical shutter illustratedin FIG. 4, according to an example embodiment;

FIG. 6 illustrates a pattern of diffraction gratings formed by the lightgenerating apparatus of FIG. 4 according to an example embodiment;

FIG. 7 illustrates a light generating apparatus including a plurality oflight sources and a plurality of optical shutters according to anexample embodiment;

FIG. 8 illustrates a light generating apparatus according to an exampleembodiment;

FIG. 9 illustrates a light generating apparatus according to an exampleembodiment; and

FIG. 10 illustrates a light generating apparatus according to an exampleembodiment.

DETAILED DESCRIPTION

Example embodiments may be embodied in many different forms and shouldnot be construed as being limited to the embodiments set forth herein;rather, these embodiments may be provided so that this disclosure willbe thorough and complete, and will fully convey the concept of exampleembodiments to those skilled in the art.

It will be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, there are nointervening elements present. As used herein the term “and/or” includesany and all combinations of one or more of the associated listed items.

It will be understood that, although the terms “first”, “second”, etc.may be used herein to describe various elements, components, regions,layers and/or sections, these elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another element, component, region, layer or section. Thus,a first element, component, region, layer or section discussed belowcould be termed a second element, component, region, layer or sectionwithout departing from the teachings of example embodiments.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of exampleembodiments. As used herein, the singular forms “a,” “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

Example embodiments are described herein with reference tocross-sectional illustrations that are schematic illustrations ofidealized embodiments (and intermediate structures) of exampleembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, example embodiments should not be construed aslimited to the particular shapes of regions illustrated herein but areto include deviations in shapes that result, for example, frommanufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the figures are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to limit the scope ofexample embodiments.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which example embodiments belong. Itwill be further understood that terms, such as those defined incommonly-used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand will not be interpreted in an idealized or overly formal senseunless expressly so defined herein.

FIG. 1 illustrates a light generating apparatus 100 according to anexample embodiment. The light generating apparatus 100 may include alight source 110, a beam expander 120, a first polarizer 131, an opticalshutter 130, a second polarizer 132 and/or a focusing lens 140.

The light source 110 may be a laser beam emitting device with improvedcoherence and/or straight features. The light source 110 may not belimited to a particular device. Examples of light source 110 may includea gas laser (e.g., a helium-neon laser and/or an excimer laser), a solidlaser (e.g., a ruby laser and/or a Nd:YAG laser) and/or a semiconductorlaser.

A light beam emitted from the light source 110 may be a polarized beam.Alternatively, the light beam emitted from the light source 110 may be anon-polarized beam, polarized by first polarizer 131. The light source110 is well known to one of ordinary skill in the art, and thus itsdescription is not given here.

The beam expander 120 may collimate the light beam emitted from thelight source 110. In particular, the beam expander 120 may enlarge thewidth of the light beam emitted from the light source 110 and/or mayconvert the light beam into parallel light so that the parallel light isincident on the optical shutter 130. The beam expander 120 may furtherinclude a collimating lens 121 in order to convert the light beamemitted from the light source 110 into light parallel to an opticalaxis.

The first polarizer 131, the optical shutter 130, and/or the secondpolarizer 132 may be sequentially disposed on the path of a light beamtransmitted through the beam expander 120.

The first and second polarizers 131 and 132 may each be a device forobtaining linearly polarized light, such as a thin plate that onlytransmits light oscillating in a desired (or, alternatively, apredetermined) direction. According to an example embodiment, the firstpolarizer 131 and/or the second polarizer 132 may have polarizationplanes perpendicular to each other. Thus, a polarized light beamtransmitted through the first polarizer 131 and a polarized light beamtransmitted through the second polarizer 132 may be perpendicular toeach other.

The optical shutter 130 may further transmit the light beam transmittedthrough the beam expander 120. The optical shutter 130 may be atransparent spatial light modulator (T-SLM) including a plurality ofpixels and may selectively transmit light according to on/off control ona pixel-by-pixel basis.

The optical shutter 130 may also include a liquid crystal display (LCD)(e.g., a thin film transistor liquid crystal display, TFT-LCD). In sucha case, an off-state may refer to a state in which a voltage is notapplied to the optical shutter 130. In an off-state, the optical shutter130 may rotate by 90 degrees the light beam from the first polarizer 131along a molecule arrangement of liquid crystals in the optical shutter130. This rotated light beam proceeds to the second polarizer 132.

On the other hand, an on-state refers to a state in which a voltage maybe applied to the optical shutter 130. In the on-state, the liquidcrystal molecules may be oriented along the direction of an electricalfield such that the light beam transmitted through the first polarizer131 is incident on the second polarizer 132 with no change inpolarization direction. Thus, in an on-state, the light beam may beblocked by the second polarizer 132.

The optical shutter 130 may include a pixel region. Thus, the light beammay be transmitted through a pixel region to which a voltage is notapplied, and/or the light beam may be blocked in a pixel region to whicha voltage is applied. Thus, the optical shutter 130 may perform acontrol operation so that a light beam can be transmitted or blocked ina desired form by selectively applying a voltage to the optical shutter130 on a pixel-by-pixel basis.

For example, in FIG. 2A, the optical shutter 130 may be controlled sothat there is a black backdrop and two openings 133 a and 133 b,represented by two white colored circles. The light beam may only passthrough the two openings 133 a and 133 b. An applied voltage may controlthe two openings 133 a and/or 133 b. The openings 133 a and/or 133 b maybe formed when no voltage is applied to the regions where said openingsreside. In contrast, openings 133 a and/or 133 b do not form when avoltage is applied to the region where said openings reside, such thatthe light beam is blocked.

As mentioned above, by controlling whether a voltage is applied to eachpixel, regions through which a light beam is to be transmitted (e.g.,the openings 133 a and/or 133 b) may be freely selected in the opticalshutter 130. In addition, by controlling whether a voltage is applied toeach pixel, the positions of the openings 133 a and/or 133 b of theoptical shutter 130 may be freely changed.

In this case, by controlling the number, size, location and/or intervalof the openings 133 a and/or 133 b (that is, an interval between theopenings 133 a and/or 133 b), a light beam incident on a photoresist(PR) 160 may be controlled so as to form a diffraction grating havingvarious periods and/or directions. A method of controlling the periodand/or direction of a diffraction grating is described below.

The focusing lens 140 may focus the two light beams transmitted throughthe optical shutter 130 (e.g., the openings 133 a and/or 133 b) so as toemit the two light beams to the photoresist 160 on a stage 150. The twolight beams transmitted through the openings 133 a and/or 133 b may befocused on the same location of the photoresist 160. Thus, the two lightbeams focused by the focusing lens 140 may interfere with each other onthe photoresist 160 to form interference patterns. The interferencepatterns may be recorded on the photoresist 160. Photoresist 160 is aphotosensitive material. A diffraction grating may be manufactured onthe photoresist 160, the interference patterns recorded on thephotoresist 160 itself. The two light beams focused by the focusing lens140 may be incident on the photoresist 160, and thus a diffractiongrating having various periods and/or directions can be formed.

The light generating apparatus 100 may further include a controller 170.The controller 170 may control the optical shutter 130 on apixel-by-pixel basis and/or may control movement of the stage 150.

Hereinafter, a method of controlling a period and/or direction of adiffraction grating will be described. FIGS. 2A through 2E illustratevarious patterns of an opening in an optical shutter 130, according toexample embodiments. FIGS. 3A through 3E illustrate patterns ofdiffraction gratings formed by light transmitted through the openings ofFIGS. 2A through 2E, according to example embodiments.

A relationship between a period of a diffraction grating and/or aninterval between the two openings displayed on the optical shutter 130is given by Equation 1.d=λ/(2n·sin θ)  (1)

Here, “d” is a period of a diffraction grating, “λ” is a wavelength oflight, and θ is an incident angle between two light beams.

According to Equation 1, when an incident angle between the two lightbeams is 90°, “d” is at a minimum since sin θ is at a maximum. On theother hand, the further θ is from 90° (that is, the closer θ is to 0° or180°) the smaller sin θ, and the greater “d”. Therefore, a diffractiongrating having a desired period may be obtained by controlling aninterval between the two the openings formed on the optical shutter 130.

For example, referring to FIGS. 2A and 2B in which two openings areformed in the optical shutter 130, the interval between two openings 133a and 133 b may be about 12.3 mm in a pattern (hereinafter, referred toas a ‘pattern 1’) of FIG. 2A, and an interval between two openings 134 aand 134 b may be about 4.09 mm in another pattern (hereinafter, referredto as a ‘pattern 2’) of FIG. 2B, which is narrower than the interval ofFIG. 2A.

FIGS. 3A through 3E illustrate patterns of diffraction gratings may beformed by light transmitted through the openings of FIGS. 2A through 2E,respectively. Table 1 shows an incident angle and a period.

TABLE 1 Pattern 1 Pattern 2 Interval between 12.3 mm 4.09 mm openingsSize of opening   30 μm   30 μm Incident angle 3.52° 1.17° Fringe period 4.3 μm   13 μm

As illustrated in FIGS. 3A and 3B and Table 1, a period of thediffraction grating (see FIG. 3A) using the optical shutter 130 having awide interval between openings may be smaller than a period of thediffraction grating (see FIG. 3B) using the optical shutter 130 having anarrow interval between openings. In other words, as an interval betweenopenings decreases, an incident angle θ between two light beams maydecrease. Thus, period “d” of the diffraction grating may increase.

As mentioned above, the direction of a diffraction grating may becontrolled by rotating the locations of two openings displayed on theoptical shutter 130. As the locations of two openings in the opticalshutter 130 rotate as illustrated in FIGS. 2B through 2E, a gratingangular orientation changes as illustrated in FIGS. 3B through 3E.

In addition, the spot size of a light beam transmitted through theoptical shutter 130 may be controlled by changing the area of theopening displayed on the optical shutter 130. Furthermore, beam shapingof a light beam transmitted through the optical shutter 130 may becontrolled by changing the shape of the opening in the optical shutter130.

As mentioned above, in the light generating apparatus 100, a diffractiongrating having various periods and/or directions may be manufactured bychanging an interval between openings in the optical shutter 130, thelocations of the openings, and/or the shapes of the openings.

In addition, since control of the openings of the optical shutter 130can be performed by turning on/off pixels on a pixel-by-pixel basis,time and/or costs for manufacturing a diffraction grating may bereduced.

Light generating apparatus 100 may include a T-SLM as the opticalshutter 130. As illustrated in FIG. 1 and discussed above, beam expander120 collimates a light beam emitted from the light source 110. Aparallel light beam transmitted through the beam expander 120 isincident on the optical shutter 130, and then is selectively transmittedby the optical shutter 130.

The optical shutter 130 may include a plurality of pixels. The pluralityof pixels may be controlled to selectively transmit light on apixel-by-pixel basis according to an on/off control. That is, a pixelregion with no applied voltage permits transmission of a light beam,while a pixel region with an applied voltage blocks the light beam.Thus, the optical shutter 130 may operate so that a light beam can betransmitted or blocked according to a desired form by selectivelyapplying a voltage to the optical shutter 130 on a pixel-by-pixel basis.

The light beam selectively transmitted through the optical shutter 130is incident on the focusing lens 140. Likewise, the light beam focusedby the focusing lens 140 is also incident on the photoresist 160 on thestage 150, thereby generating a diffraction grating having variousperiods and/or directions.

FIG. 4 illustrates a light generating apparatus 101 according to anotherexample embodiment. FIG. 5 illustrates openings in an optical shutter130 illustrated in FIG. 4, according to another example embodiment. FIG.6 illustrates a pattern of diffraction gratings formed by the lightgenerating apparatus 101 of FIG. 4, according to an example embodiment.

Referring to FIGS. 4 and 5, a plurality of openings 135 a through 135 dmay be formed in the optical shutter 130 of the light generatingapparatus 101. If a plurality of openings are formed in the opticalshutter 130, and/or light beams are selectively transmitted, a multidiffraction grating may be formed, as illustrated in FIG. 6. By forminga plurality of openings, a multi beam may be easily formed, and thus aninterference pattern can be formed on the photoresist 160. In addition,using the interference pattern, two-dimensional and/or three-dimensionalphotonic crystal type patterns, which to date are not easilymanufactured, may be manufactured.

As illustrated in FIG. 7, when a plurality of light sources 110 ₁through 110 _(n) and/or a plurality of optical shutters 130 ₁ through130 _(n) are arranged in an array type, a large-sized pattern may beembodied. Furthermore, when the light sources 110 ₁ through 110 _(n)and/or the optical shutters 130 ₁ through 130 _(n) are arranged in thearray type, a nano pattern partially having various shapes may bemanufactured.

FIG. 8 illustrates a light generating apparatus 200 according to anotherexample embodiment.

Referring to FIG. 8, the light generating apparatus 200 may include alight source 210, a beam expander 220, a beam splitter 235, an opticalshutter 230, a polarizer 231 and/or a focusing lens 240. The lightgenerating apparatus 200 may be different from the light generatingapparatus 100 of FIG. 1. For example, the light generating apparatus 200may further include the beam splitter 235, and/or the optical shutter230 may be liquid crystal on silicon (LCoS), which may be a reflectivespatial light modulator (R-SLM).

The optical shutter 230 may include a plurality of pixels, and canselectively transmit light by turning on/off pixels on a pixel-by-pixelbasis.

Hereinafter, operating processes of the light generating apparatus 200including an R-SLM as the optical shutter 230 will be described.

First, a light beam emitted from the light source 210 may be collimatedby the beam expander 220. A parallel light beam transmitted through thebeam expander 220 may be incident on the beam splitter 235. The beamsplitter 235 may divide the incident light and/or may provide theincident light beam to the optical shutter 230. In addition, the beamsplitter 235 may provide a light beam reflected by the optical shutter230 to the focusing lens 240. To achieve this, the beam splitter 235 mayhave surfaces facing the beam expander 220, the optical shutter 230,and/or the focusing lens 240, respectively.

For example, a general beam splitter, which divides the intensity ofincident light in half by transmitting some of the light beams and/orreflecting the remaining light beams, may be used as the beam splitter235. The light beam transmitted through the beam splitter 235 may beincident on the optical shutter 230.

In the present embodiment, since an R-SLM may be used as the opticalshutter 230, when a light beam is incident on the optical shutter 230and/or the optical shutter 230 is in an off-state (no voltage applied),the optical shutter 230 may rotate by 90 degrees and reflect the lightbeam. On the other hand, in an on-state (voltage applied), the lightbeam incident on the optical shutter 230, which is polarized light, maybe reflected with no change. The light beam reflected by the opticalshutter 230 may be incident on the beam splitter 235. The light beamincident on the beam splitter 235 may be reflected by a coated surface235 a of the beam splitter 235. Then, a first part of the light beamreflected by the coated surface 235 a, which is reflected with nochange, may be absorbed by the polarizer 231. A second part of the lightbeam reflected by the coated surface 235 a, which is rotated by 90degrees, may be transmitted through the polarizer 231 to be incident onthe focusing lens 240. Then, a light beam focused by the focusing lens240 may be incident on a photoresist 260 on a stage 250. At this time,using an interference pattern formed on the photoresist 260, adiffraction grating having various periods and/or directions may beformed.

FIG. 9 illustrates a light generating apparatus 201 according to anotherexample embodiment.

Referring to FIG. 9, the light generating apparatus 201 may include alight source 210, a beam expander 220, a polarization beam splitter 236,an optical shutter 230 and/or a focusing lens 240.

The light generating apparatus 201 may be different from the lightgenerating apparatus 200 of FIG. 8 in that the light generatingapparatus 201 may further include the polarization beam splitter 236.The optical shutter 230 may be a liquid crystal type modulator such asan LCoS, which is an R-SLM.

Hereinafter, operating processes of the light generating apparatus 201including an R-SLM as the optical shutter 230 and the polarization beamsplitter 236 are described.

First, a light beam emitted from the light source 210 is collimated bythe beam expander 220. A parallel light beam transmitted through thebeam expander 220 is divided by the polarization beam splitter 236.

In particular, the polarization beam splitter 236 may be a beam splitterreflecting an S-polarized light beam and/or transmitting a P-polarizedlight beam. In this case, a light beam emitted from the light source 210may be a P-polarized light beam so as to proceed towards the opticalshutter 230. A light beam transmitted through the polarization beamsplitter 236 may be incident on the optical shutter 230.

In the present embodiment, since the optical shutter 230 may be an R-SLMlike the case of FIG. 8, a light beam incident on the optical shutter230 may rotate by 90 degrees and/or may be reflected (S-polarization) inan off-state in which a voltage is not applied. On the other hand, in anon-state in which a voltage is applied, the light beam incident on theoptical shutter 230, which is polarized light (P-polarization), may bereflected with no change. The light beam reflected by the opticalshutter 230 may be incident back on the polarization beam splitter 236.Only a light beam, which is an S-polarized light beam, is reflected by acoated surface 236 a to be incident on the focusing lens 240. Also, when(i) a quarter wave plate (not shown) is disposed between thepolarization beam splitter 236 and the optical shutter 230, and (ii) theoptical shutter 230 provides optical signals opposite to the opticalsignals illustrated in FIG. 8, the same effect as the case of FIG. 8 cannevertheless be obtained. That is, in FIG. 9, a light beam rotated bythe optical shutter 230 by 90 degrees may be transmitted through thepolarization beam splitter 236, and/or only a an unchanged light beam,reflected by the optical shutter 230, may be reflected by thepolarization beam splitter 236 to be incident on the focusing lens 240.

A light beam focused by the focusing lens 240 may be incident on thephotoresist 260 on a stage 250, and thus a diffraction grating havingvarious periods and/or directions can be formed.

FIG. 10 illustrates a light generating apparatus 202 according toanother example embodiment. In FIG. 10, the light generating apparatus202 may include a light source 210, a beam expander 220, a beam splitter235, an optical shutter 230′ and/or a focusing lens 240. The lightgenerating apparatus 202 may be different from the light generatingapparatus 201 of FIG. 9 in that the optical shutter 230′ may be a MEMStype modulator such as a digital micro-device (DMD), which is an R-SLM.

Operating processes of the light generating apparatus 202 may include anR-SLM as the optical shutter 230′. First, a light beam emitted from thelight source 210 may be collimated by the beam expander 220. A parallellight beam transmitted through the beam expander 220 may be divided bythe beam splitter 235 and then emitted to the optical shutter 230.

In the present example embodiment, since the optical shutter 230′ is anMEMS type modulator, desired pixel regions may reflect light beamstowards the beam splitter 235, and the other non-desired pixel regionsmay not reflect light beams towards the beam splitter 235. A light beamincident on the beam splitter 235 may be reflected by a coated surface235 a to be incident on the focusing lens 240. When a polarization beamsplitter and/or a quarter wave plate are used instead of the beamsplitter 235, the same effect illustrated in FIG. 10 may be obtained.Otherwise, the light beams not reflected toward the beam splitter 235may not be incident on the focusing lens 240.

A light beam focused by the focusing lens 240 may be incident on aphotoresist 260 on a stage 250, and thus a diffraction grating havingvarious periods and/or directions can be formed.

Like in the case of FIG. 1, in FIGS. 8 through 10, a diffraction gratinghaving various periods and/or directions may be manufactured by changingan interval between openings displayed on the optical shutters 230 and230′. In addition, since control of the openings of the optical shutter230 may be performed by turning on/off pixels on a pixel-by-pixel basis,time and/or costs for manufacturing a diffraction grating may bereduced.

As described above in the description of the example embodiments, theoptical shutter may be controlled by electrical driving method ratherthan a mechanical driving method. In addition, various nano patterns maybe easily formed by adjusting a portion of the optical shutter. Forexample, the optical shutter may be adjusted to permit openings throughwhich a light beam is transmitted, the locations of the openings, and/orthe shapes of the openings. Thus, since time and/or costs formanufacturing a diffraction grating may be reduced, the industrialeffective value of the diffraction grating may be improved.

The described example embodiments are descriptive only and are notnon-limiting. Descriptions of features or aspects within each exampleembodiment should typically be considered as available for other similarfeatures or aspects in other embodiments.

What is claimed is:
 1. A light generating apparatus comprising: a lightsource emitting a light beam; a beam expander that enlarges andcollimates the light beam; an optical shutter configured to selectivelytransmit a light beam coming from the beam expander to form at least twonon-diffracted light beams; and a focusing lens focusing the at leasttwo light beams on a same location such that the at least two lightbeams interfere with each other to form a diffraction grating pattern onthe location, and wherein the optical shutter includes a plurality ofpixels such that the optical shutter selectively transmits a light beamaccording to an on/off control, wherein the on/off control operates on apixel-by-pixel basis and is configured to form at least two opticalopenings in the optical shutter such that the light beam coming from thebeam expander is selectively transmitted through the openings, the atleast two openings being separated by at least one pixel from eachother, and wherein the on/off control adjusts at least one of aninterval between the at least two openings, sizes of at least one of theat least two openings, locations of at least one of the at least twoopenings, and shapes of at least one of the at least two openings,wherein a period and a direction of the diffraction grating pattern arecontrolled according to only the on/off control of the optical shutter.2. The light generating apparatus of claim 1, wherein a first portion ofthe optical shutter transmits the light beam transmitted through thebeam expander, and a second portion of optical shutter does not transmitthe light beam transmitted through the beam expander.
 3. The lightgenerating apparatus of claim 1, wherein the focusing lens focuses theat least two light beams transmitted through the focusing lens on aphotosensitive layer, and forms the diffraction grating pattern using aninterference pattern formed on the photosensitive layer by interferenceof the focused at least two light beams.
 4. The light generatingapparatus of claim 1, wherein the optical shutter further includes aspatial light modulator.
 5. The light generating apparatus of claim 1,wherein the beam expander further includes a collimating lens changingthe light beam emitted from the light source into a parallel light beam.6. The light generating apparatus of claim 1, wherein the lightgenerating apparatus further includes a plurality of light sources and aplurality of optical shutters, the plurality of light sources and theplurality of optical shutters arranged in an array shape.
 7. The lightgenerating apparatus of claim 1 further comprising: a beam splitterhaving surfaces facing the beam expander, the optical shutter and thefocusing lens, providing the light beam coming from the beam expander tothe optical shutter, and providing the at least two light beams emittedfrom the optical shutter to the focusing lens.
 8. The light generatingapparatus 7, further comprising: a polarizer polarizing the at least twolight beams provided by the beam splitter, the polarizer being betweenthe beam splitter and the focusing lens.
 9. The light generatingapparatus 7, wherein the beam splitter further includes a polarizationbeam splitter.
 10. The light generating apparatus 7, wherein the opticalshutter further includes at least one of a liquid crystal on silicon(LCoS) and a digital micro mirror device (DMD).
 11. A light generatingapparatus for manufacturing a nano diffraction grating patterncomprising: an apparatus configured to selectively provide a light beamand including an on/off control; an optical shutter including aplurality of pixels, the on/off control configured to control theoptical shutter on a pixel-by-pixel basis, wherein the optical shutteris configured to at least one of selectively transmit and selectivelyreflect the light beam to form at least two non-diffracted light beamsseparated by at least one pixel from each other on the optical shutter;and a stage configured to mount a photosensitive layer thereon, thephotosensitive layer configured to receive the at least two light beamssuch that the at least two light beams interfere with each other to formthe nano diffraction grating pattern on the photosensitive layer,wherein a period and a direction of the nano diffraction grating patternare controlled according to only the on/off control of the opticalshutter.
 12. A method of controlling a light generating apparatus, themethod comprising: emitting a light beam from a light source; enlargingthe light beam emitted from the light source; collimating the light beamemitted from the light source; selectively transmitting a collimatedlight beam to form at least two non-diffracted light beams; and focusingthe at least two light beams on a same location such that the at leasttwo light beams interfere with each other to form a diffraction gratingpattern on the location, and wherein the selectively transmitting isperformed on a pixel-by-pixel basis by an on/off control, the on/offcontrol controlling an optical shutter including a plurality of pixels,wherein the selectively transmitting is performed by controlling theoptical shutter, on which at least two openings separated by at leastone pixel from each other are to be formed, so that only a light beamincident on the openings is transmitted through the optical shutter, andwherein the on/off control adjusts at least one of an interval betweenthe at least two openings, sizes of at least one of the at least twoopenings, locations of at least one of the at least two openings, andshapes of at least one of the at least two openings, wherein a periodand a direction of the diffraction grating pattern are controlledaccording to only the on/off control of the optical shutter.
 13. Themethod of claim 12, wherein the selectively transmitting furthercomprises: dividing the light beam by a beam splitter; and selectivelyreflecting a divided light beam by an optical shutter.